/*
 *  NFCSigning - Open source library for signing/validation of NDEF messages
 *  Copyright (C) 2009-2010 The NFCSigning Team
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */
package org.nfcsigning.algorithm;

import java.security.DigestException;
import java.security.MessageDigest;
import org.bouncycastle.crypto.Digest;

/**
 *
 * @author Markus Kilås
 */
public class SatsaSha1Digest implements Digest {

    private MessageDigest md;

    public SatsaSha1Digest(MessageDigest messageDigest) {
        this.md = messageDigest;
    }
    
    public String getAlgorithmName() {
        return "SHA-1";
    }

    public int getDigestSize() {
        return 20;
    }

    public void update(byte in) {
        md.update(new byte[]{in}, 0, 1);
    }

    public void update(byte[] in, int inOff, int len) {
        md.update(in, inOff, len);
    }

    public int doFinal(byte[] out, int outOff) {
        try {
            return md.digest(out, outOff, 20);
        } catch (DigestException ex) {
            return 0;
        }
    }

    public void reset() {
        md.reset();
    }

}
